Abstract: Objective To investigate the mechanism of reversing effect of epigalloca techin gallate(EGCG)on multi-drug resistance(MDR)of human hepa to cellular carcinoma(HCC)cell lines Bel-FU,and to provide the reference for screening natural drugs for reversing the MDR of HCC at transc riptional level.Methods Human HCC cell line BEL-7402 and multidrug-resistant HCC cell line Bel-Fu were cultured for the study.The MDR of Bel-Fu cells and its drug sensitivity to EGCG were determined by methyl thiazolyl tetrazolium(MTT)assay.Confined to the scope of the development of HCC,the 42 gene expression profiles of BEL-7402 group,BeL-FU group,and BeL-FU EGCG group were detected by real-time quantitative-PCR array.The expression profiles of gene Hras,MDR1 were comfirmed by real-time quantitative polym erase chain reaction.Results The resistance index(IR)of Bel-Fu to 5-fluo rouracil,cytarabine,vincristin,doxorubicin,daunorubicin was 89.6,3.9,37.2,16.5,and 3.7,respectively.The 50% inhibitory concentration(IC50)and 10% inhibitory concentration(IC10)of EGCG was 587.4μg/mL and 83.1 μg/mL,respectively.Compared with those in BEL-7402 group,5 differentially expressed genes were up-regulated in Bel-Fu group.Compared with those in Bel-Fu group,6 differentially expressed genes were down-regulated in Bel-Fu EGCG group.Compared with those in BEL-7402 group,the expression profiles of gene Hras and MDR1 in Bel-Fu group showed 2.7 and 2.74 times of increase.Compared with those in Bel-Fu group,the expression profiles of gene Hras and MDR1 in the Bel-Fu EGCG group decreased by 2.37 and 2.63 times.Conclusion EGCG could reverse the MDR of human hepatocellular carcinoma cell lines Bel-FU.